python - Need regex for a period that's not between numbers -

need regex periods that's not between 2 numbers

it should match

• happy1...

• hello, world.

but should not match:

• 1.2
• holiday

this work you:

((?<!\d)\.|\.(?!\d)) 

it matches period isn't preceded digit ((?<!\d)\.) or (|) isn't followed 1 (\.(?!\d)).

actual python code:

import re p = re.compile(ur'((?<!\d)\.|\.(?!\d))') test_str = u"happy1...\nhello, world.\n1.2\nholiday"  re.findall(p, test_str) 

demo

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